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Gatica S, Fuentes B, Rivera-Asín E, Ramírez-Céspedes P, Sepúlveda-Alfaro J, Catalán EA, Bueno SM, Kalergis AM, Simon F, Riedel CA, Melo-Gonzalez F. Novel evidence on sepsis-inducing pathogens: from laboratory to bedside. Front Microbiol 2023; 14:1198200. [PMID: 37426029 PMCID: PMC10327444 DOI: 10.3389/fmicb.2023.1198200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 06/05/2023] [Indexed: 07/11/2023] Open
Abstract
Sepsis is a life-threatening condition and a significant cause of preventable morbidity and mortality globally. Among the leading causative agents of sepsis are bacterial pathogens Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, and Streptococcus pyogenes, along with fungal pathogens of the Candida species. Here, we focus on evidence from human studies but also include in vitro and in vivo cellular and molecular evidence, exploring how bacterial and fungal pathogens are associated with bloodstream infection and sepsis. This review presents a narrative update on pathogen epidemiology, virulence factors, host factors of susceptibility, mechanisms of immunomodulation, current therapies, antibiotic resistance, and opportunities for diagnosis, prognosis, and therapeutics, through the perspective of bloodstream infection and sepsis. A list of curated novel host and pathogen factors, diagnostic and prognostic markers, and potential therapeutical targets to tackle sepsis from the research laboratory is presented. Further, we discuss the complex nature of sepsis depending on the sepsis-inducing pathogen and host susceptibility, the more common strains associated with severe pathology and how these aspects may impact in the management of the clinical presentation of sepsis.
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Affiliation(s)
- Sebastian Gatica
- Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Brandon Fuentes
- Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Elizabeth Rivera-Asín
- Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Paula Ramírez-Céspedes
- Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Javiera Sepúlveda-Alfaro
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Eduardo A. Catalán
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Susan M. Bueno
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alexis M. Kalergis
- Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Endocrinología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Felipe Simon
- Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Claudia A. Riedel
- Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Felipe Melo-Gonzalez
- Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
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Powell LC, Adams JYM, Quoraishi S, Py C, Oger A, Gazze SA, Francis LW, von Ruhland C, Owens D, Rye PD, Hill KE, Pritchard MF, Thomas DW. Alginate oligosaccharides enhance the antifungal activity of nystatin against candidal biofilms. Front Cell Infect Microbiol 2023; 13:1122340. [PMID: 36798083 PMCID: PMC9927220 DOI: 10.3389/fcimb.2023.1122340] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 01/11/2023] [Indexed: 02/04/2023] Open
Abstract
Background The increasing prevalence of invasive fungal infections in immuno-compromised patients is a considerable cause of morbidity and mortality. With the rapid emergence of antifungal resistance and an inadequate pipeline of new therapies, novel treatment strategies are now urgently required. Methods The antifungal activity of the alginate oligosaccharide OligoG in conjunction with nystatin was tested against a range of Candida spp. (C. albicans, C. glabrata, C. parapsilosis, C. auris, C. tropicalis and C. dubliniensis), in both planktonic and biofilm assays, to determine its potential clinical utility to enhance the treatment of candidal infections. The effect of OligoG (0-6%) ± nystatin on Candida spp. was examined in minimum inhibitory concentration (MIC) and growth curve assays. Antifungal effects of OligoG and nystatin treatment on biofilm formation and disruption were characterized using confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and ATP cellular viability assays. Effects on the cell membrane were determined using permeability assays and transmission electron microscopy (TEM). Results MIC and growth curve assays demonstrated the synergistic effects of OligoG (0-6%) with nystatin, resulting in an up to 32-fold reduction in MIC, and a significant reduction in the growth of C. parapsilosis and C. auris (minimum significant difference = 0.2 and 0.12 respectively). CLSM and SEM imaging demonstrated that the combination treatment of OligoG (4%) with nystatin (1 µg/ml) resulted in significant inhibition of candidal biofilm formation on glass and clinical grade silicone surfaces (p < 0.001), with increased cell death (p < 0.0001). The ATP biofilm disruption assay demonstrated a significant reduction in cell viability with OligoG (4%) alone and the combined OligoG/nystatin (MIC value) treatment (p < 0.04) for all Candida strains tested. TEM studies revealed the combined OligoG/nystatin treatment induced structural reorganization of the Candida cell membrane, with increased permeability when compared to the untreated control (p < 0.001). Conclusions Antimicrobial synergy between OligoG and nystatin against Candida spp. highlights the potential utility of this combination therapy in the prevention and topical treatment of candidal biofilm infections, to overcome the inherent tolerance of biofilm structures to antifungal agents.
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Affiliation(s)
- Lydia C. Powell
- Advanced Therapies Group, Cardiff University School of Dentistry, Cardiff, United Kingdom
- Microbiology and Infectious Disease group, Swansea University Medical School, Swansea, United Kingdom
- *Correspondence: Lydia C. Powell,
| | - Jennifer Y. M. Adams
- Advanced Therapies Group, Cardiff University School of Dentistry, Cardiff, United Kingdom
| | - Sadik Quoraishi
- Otolaryngology Department, New Cross Hospital, Wolverhampton, United Kingdom
| | - Charlène Py
- Advanced Therapies Group, Cardiff University School of Dentistry, Cardiff, United Kingdom
- School of Engineering, University of Angers, Angers, France
| | - Anaϊs Oger
- Advanced Therapies Group, Cardiff University School of Dentistry, Cardiff, United Kingdom
- School of Engineering, University of Angers, Angers, France
| | - Salvatore A. Gazze
- Centre for Nanohealth, Swansea University Medical School, Swansea, United Kingdom
| | - Lewis W. Francis
- Centre for Nanohealth, Swansea University Medical School, Swansea, United Kingdom
| | - Christopher von Ruhland
- Central Biotechnology Services, Cardiff University School of Medicine, Cardiff, United Kingdom
| | - David Owens
- Head and Neck Directorate, University Hospital of Wales, Cardiff, United Kingdom
| | | | - Katja E. Hill
- Advanced Therapies Group, Cardiff University School of Dentistry, Cardiff, United Kingdom
| | - Manon F. Pritchard
- Advanced Therapies Group, Cardiff University School of Dentistry, Cardiff, United Kingdom
| | - David W. Thomas
- Advanced Therapies Group, Cardiff University School of Dentistry, Cardiff, United Kingdom
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Wang JX, Yu SH, Hall RR, McNiff J, Leffell DJ, Kibbi N. Verrucous candidiasis of the lip: A harbinger of squamous cell carcinoma. JAAD Case Rep 2021; 16:168-170. [PMID: 34646926 PMCID: PMC8498090 DOI: 10.1016/j.jdcr.2021.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Affiliation(s)
- Jake X Wang
- Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut
| | - Sherry H Yu
- Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut
| | - Rebecca R Hall
- The Dermatology Center of Stamford, Stamford, Connecticut
| | - Jennifer McNiff
- Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut.,Department of Pathology, Yale University School of Medicine, New Haven, Connecticut
| | - David J Leffell
- Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut
| | - Nour Kibbi
- Department of Dermatology, Stanford University, Redwood City, California
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Zhang W, Wu S, Wang X, Gao Y, Yan Z. Malignant Transformation and Treatment Recommendations of Chronic Hyperplastic Candidiasis-A Six-year Retrospective Cohort Study. Mycoses 2021; 64:1422-1428. [PMID: 34553417 DOI: 10.1111/myc.13371] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/15/2021] [Accepted: 09/19/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Oral chronic hyperplastic candidiasis (CHC) is the most uncommon type of oral candidiasis with diverse manifestations. Up to date the diagnosis, long-term management and prognosis of this oral potentially malignant disorder remain obscure. OBJECTIVES The aim of this study was to provide the recommendations guiding the diagnostic procedure, clinical management and prognosis assessment of CHC. METHODS A retrospective cohort study was performed during January 2015 to April 2021 involving patients with a definite diagnosis of CHC in the Department of Oral Medicine of Peking University School and Hospital of Stomatology. Demographic features, clinical and histopathological features, treatment protocols and follow-ups including malignancy transformation were analysed. RESULTS Fourty eight CHC patients were collected and reviewed, with a male-to-female ratio of 2.69:1. The average age at diagnosis was 54.92 ± 9.79 (36-80) years old. Clinically, the multiform oral lesions were diverse and frequently presented as white plaque and erythematous lesions. As a result, the initial diagnostic accordance rate was only 54.17%, and the most common presumptive initial diagnoses were oral lichen planus (22.92%), oral leukoplakia (20.83%) and traumatic lesion (2.08%). Histopathologically, ten (20.83%) patients had varying degrees of epithelial dysplasia, and two (4.17%) patients had malignant transformation with a mean transformation time of 6.5 ± 6.36 months. Among the 28 patients who underwent fungal culture, 24 patients were exclusively infected by Candida albicans, with two patients each mixed infected by C glabrata and C tropicalis, respectively. Notably, treatment with fluconazole had the lower recurrence rate compared with topical nystatin. CONCLUSIONS The diagnosis and management of CHC remain a challenge due to its polymorphic clinical presentations, chronic progression and potential of malignant transformation.
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Affiliation(s)
- Wenqing Zhang
- Department of Oral Medicine, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China
| | - Shuangshuang Wu
- Department of Oral Medicine, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China
| | - Xu Wang
- Department of Oral Medicine, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China
| | - Yan Gao
- Department of Oral Pathology, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China
| | - Zhimin Yan
- Department of Oral Medicine, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China
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Liao M, Cheng L, Zhou XD, Ren B. [Research progress of Candida albicans on malignant transformation of oral mucosal diseases]. HUA XI KOU QIANG YI XUE ZA ZHI = HUAXI KOUQIANG YIXUE ZAZHI = WEST CHINA JOURNAL OF STOMATOLOGY 2020; 38:431-437. [PMID: 32865364 DOI: 10.7518/hxkq.2020.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Oral cancer is the most common malignant tumor in the head and neck, and is one of the world's top ten malignancies. Microbial infection is an important risk factor of oral cancer. Candida albicans is the most popular opportunistic fungal pathogen. Epidemiological studies have shown that Candida albicans is closely tied to oral malignancy. Animal experimentation have also proven that infection of Candida albicans can promote the development of oral epithelial carcinogenesis. The current studies have revealed several mechanisms involved in this process, including destroying the epithelial barrier, producing carcinogenic substances (nitrosamines, acetaldehyde), inducing chronic inflammation, activating immune response, etc. However, current researches on mechanisms are still inadequate, and some hypotheses remain controversial. Here, we review the findings related to Candida albicans' effect on the malignant transformation of oral mucosa, hoping to provide reference for deep research and controlling oral cancer clinically.
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Affiliation(s)
- Min Liao
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
| | - Lei Cheng
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
| | - Xue-Dong Zhou
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
| | - Biao Ren
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Dept. of Conservative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
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Kadosh D, Mundodi V. A Re-Evaluation of the Relationship between Morphology and Pathogenicity in Candida Species. J Fungi (Basel) 2020; 6:jof6010013. [PMID: 31940968 PMCID: PMC7151024 DOI: 10.3390/jof6010013] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 12/25/2022] Open
Abstract
Many pathogenic Candida species possess the ability to undergo a reversible morphological transition from yeast to filamentous cells. In Candida albicans, the most frequently isolated human fungal pathogen, multiple lines of evidence strongly suggest that this transition is associated with virulence and pathogenicity. While it has generally been assumed that non-albicans Candida species (NACS) are less pathogenic than C. albicans, in part, because they do not filament as well, definitive evidence is lacking. Interestingly, however, a recent study suggests that filamentation of NACS is associated with reduced, rather than increased, pathogenicity. These findings, in turn, challenge conventional views and suggest that there are fundamental evolutionary differences in the morphology–pathogenicity relationship in C. albicans vs. NACS. The findings also raise many new and intriguing questions and open new avenues for future research, which are discussed.
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Second primary squamous cell carcinoma in an oral cavity free flap: A case report and review of the literature. ORAL AND MAXILLOFACIAL SURGERY CASES 2019. [DOI: 10.1016/j.omsc.2019.100103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Mahalakshmi K, Sankari S. Oral Candidal Carriage Among Patients with Oral Squamous Cell Carcinoma: A Case-Control Study. JOURNAL OF OROFACIAL SCIENCES 2019. [DOI: 10.4103/jofs.jofs_69_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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9
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Pritchard M, Jack A, Powell L, Sadh H, Rye P, Hill K, Thomas D. Alginate oligosaccharides modify hyphal infiltration ofCandida albicansin anin vitromodel of invasive human candidosis. J Appl Microbiol 2017. [DOI: 10.1111/jam.13516] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- M.F. Pritchard
- Advanced Therapies Group; Cardiff University School of Dentistry; College of Biomedical and Life Sciences; Cardiff UK
| | - A.A. Jack
- Advanced Therapies Group; Cardiff University School of Dentistry; College of Biomedical and Life Sciences; Cardiff UK
| | - L.C. Powell
- Advanced Therapies Group; Cardiff University School of Dentistry; College of Biomedical and Life Sciences; Cardiff UK
| | - H. Sadh
- Advanced Therapies Group; Cardiff University School of Dentistry; College of Biomedical and Life Sciences; Cardiff UK
| | | | - K.E. Hill
- Advanced Therapies Group; Cardiff University School of Dentistry; College of Biomedical and Life Sciences; Cardiff UK
| | - D.W. Thomas
- Advanced Therapies Group; Cardiff University School of Dentistry; College of Biomedical and Life Sciences; Cardiff UK
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10
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Banerjee S, Tian T, Wei Z, Peck KN, Shih N, Chalian AA, O'Malley BW, Weinstein GS, Feldman MD, Alwine J, Robertson ES. Microbial Signatures Associated with Oropharyngeal and Oral Squamous Cell Carcinomas. Sci Rep 2017; 7:4036. [PMID: 28642609 PMCID: PMC5481414 DOI: 10.1038/s41598-017-03466-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 04/26/2017] [Indexed: 12/18/2022] Open
Abstract
The microbiome is fundamentally one of the most unique organs in the human body. Dysbiosis can result in critical inflammatory responses and result in pathogenesis contributing to neoplastic events. We used a pan-pathogen array technology (PathoChip) coupled with next-generation sequencing to establish microbial signatures unique to human oral and oropharyngeal squamous cell carcinomas (OCSCC/OPSCC). Signatures for DNA and RNA viruses including oncogenic viruses, gram positive and negative bacteria, fungi and parasites were detected. Cluster and topological analyses identified 2 distinct groups of microbial signatures related to OCSCCs/OPSCCs. Results were validated by probe capture next generation sequencing; the data from which also provided a comprehensive map of integration sites and chromosomal hotspots for micro-organism genomic insertions. Identification of these microbial signatures and their integration sites may provide biomarkers for OCSCC/OPSCC diagnosis and prognosis as well as novel avenues for study of their potential role in OCSCCs/OPSCCs.
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Affiliation(s)
- Sagarika Banerjee
- Department of Otorhinolaryngology-Head and neck surgery, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Tian Tian
- Department of Computer Science, New Jersey Institute of Technology, New Jersey, 07102, United States of America
| | - Zhi Wei
- Department of Computer Science, New Jersey Institute of Technology, New Jersey, 07102, United States of America
| | - Kristen N Peck
- Department of Otorhinolaryngology-Head and neck surgery, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Natalie Shih
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, 19104, Philadelphia, Pennsylvania, United States of America
| | - Ara A Chalian
- Department of Otorhinolaryngology-Head and neck surgery, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Bert W O'Malley
- Department of Otorhinolaryngology-Head and neck surgery, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Gregory S Weinstein
- Department of Otorhinolaryngology-Head and neck surgery, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Michael D Feldman
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, 19104, Philadelphia, Pennsylvania, United States of America
| | - James Alwine
- Department of Cancer Biology, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Erle S Robertson
- Department of Otorhinolaryngology-Head and neck surgery, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America.
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Gabrielli E, Roselletti E, Luciano E, Sabbatini S, Mosci P, Pericolini E. Comparison between bioluminescence imaging technique and CFU count for the study of oropharyngeal candidiasis in mice. Cytometry A 2015; 87:428-36. [DOI: 10.1002/cyto.a.22666] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 03/02/2015] [Accepted: 03/06/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Elena Gabrielli
- Microbiology Section; Department of Experimental Medicine; University of Perugia; Perugia Italy
| | - Elena Roselletti
- Microbiology Section; Department of Experimental Medicine; University of Perugia; Perugia Italy
| | - Eugenio Luciano
- Microbiology Section; Department of Experimental Medicine; University of Perugia; Perugia Italy
| | - Samuele Sabbatini
- Microbiology Section; Department of Experimental Medicine; University of Perugia; Perugia Italy
| | - Paolo Mosci
- Internal Medicine; Department of Pathology; Diagnostic and Veterinary Clinic; University of Perugia; Perugia Italy
| | - Eva Pericolini
- Microbiology Section; Department of Experimental Medicine; University of Perugia; Perugia Italy
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Alnuaimi AD, Wiesenfeld D, O'Brien-Simpson NM, Reynolds EC, McCullough MJ. Oral Candida colonization in oral cancer patients and its relationship with traditional risk factors of oral cancer: a matched case-control study. Oral Oncol 2014; 51:139-45. [PMID: 25498921 DOI: 10.1016/j.oraloncology.2014.11.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Revised: 11/02/2014] [Accepted: 11/12/2014] [Indexed: 10/24/2022]
Abstract
OBJECTIVES Candida, an opportunistic fungal pathogen, has been implicated in oral and oesophageal cancers. This study aimed to examine oral Candida carriage in 52 oral cancer patients and 104 age-, gender- and denture status-matched oral cancer-free subjects. MATERIAL AND METHODS We assessed general health, smoking and alcohol drinking habits, use of alcohol-containing mouthwash and periodontal status (community periodontal index of treatment needs). Yeasts were isolated using oral rinse technique and genetically identified via Real-Time PCR-High resolution melting curve analysis of conserved ribosomal DNA. Conditional and binary logistic regressions were used to identify explanatory variables that are risk factors for oral cancer. RESULTS AND CONCLUSION The frequencies of oral yeasts' presence and high oral colonization were significantly higher in oral cancer than non-oral cancer patients (p=001; p=0.033, respectively). No significant difference in the isolation profile of Candida species was found between the two groups, except C. parapsilosis was more frequent in non-oral cancer group. Differences were noticed in the incidence of C. albicans strains where significantly more C. albicans genotype-A was isolated from cancer patients and significantly more C. albicans genotype-B isolated from non-cancer patients. Multiple regression analyses showed significant association with cancer observed for alcohol drinking (OR=4.253; 95% CI=1.351, 13.386), Candida presence (OR=3.242; 95% CI=1.505, 6.984) and high oral colonization (OR=3.587; 95% CI=1.153, 11.162). These results indicate that there is a significant association between oral cancer occurrence and Candida oral colonization and that the observed genotypic diversity of C. albicans strains may play a role in oral carcinogenesis.
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Affiliation(s)
- Ali D Alnuaimi
- Melbourne Dental School, Oral Health CRC, The University of Melbourne, Melbourne, Vic 3010, Australia
| | - David Wiesenfeld
- Melbourne Dental School, Oral Health CRC, The University of Melbourne, Melbourne, Vic 3010, Australia; Head and Neck Oncology, The Royal Melbourne Hospital, Melbourne, Vic 3010, Australia
| | - Neil M O'Brien-Simpson
- Melbourne Dental School, Oral Health CRC, The University of Melbourne, Melbourne, Vic 3010, Australia
| | - Eric C Reynolds
- Melbourne Dental School, Oral Health CRC, The University of Melbourne, Melbourne, Vic 3010, Australia
| | - Michael J McCullough
- Melbourne Dental School, Oral Health CRC, The University of Melbourne, Melbourne, Vic 3010, Australia.
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13
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Boros-Majewska J, Salewska N, Borowski E, Milewski S, Malic S, Wei XQ, Hayes AJ, Wilson MJ, Williams DW. Novel Nystatin A₁ derivatives exhibiting low host cell toxicity and antifungal activity in an in vitro model of oral candidosis. Med Microbiol Immunol 2014; 203:341-55. [PMID: 24924305 DOI: 10.1007/s00430-014-0343-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 05/21/2014] [Indexed: 12/21/2022]
Abstract
Opportunistic oral infections caused by Candida albicans are frequent problems in immunocompromised patients. Management of such infections is limited due to the low number of antifungal drugs available, their relatively high toxicity and the emergence of antifungal resistance. Given these issues, our investigations have focused on novel derivatives of the antifungal antibiotic Nystatin A1, generated by modifications at the amino group of this molecule. The aims of this study were to evaluate the antifungal effectiveness and host cell toxicity of these new compounds using an in vitro model of oral candidosis based on a reconstituted human oral epithelium (RHOE). Initial studies employing broth microdilution, revealed that against planktonic C. albicans, Nystatin A1 had lower minimal inhibitory concentration than novel derivatives. However, Nystatin A1 was also markedly more toxic against human keratinocyte cells. Interestingly, using live/dead staining to assess C. albicans and tissue cell viability after RHOE infection, Nystatin A1 derivatives were more active against Candida with lower toxicity to epithelial cells than the parent drug. Lactate dehydrogenase activity released by the RHOE indicated a fourfold reduction in tissue damage when certain Nystatin derivatives were used compared with Nystatin A1. Furthermore, compared with Nystatin A1, colonisation of the oral epithelium by C. albicans was notably reduced by the new polyenes. In the absence of antifungal agents, confocal laser scanning microscopy showed that C. albicans extensively invaded the RHOE. However, the presence of the novel derivatives greatly reduced or totally prevented this fungal invasion.
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Affiliation(s)
- Joanna Boros-Majewska
- Department of Pharmaceutical Technology and Biochemistry, Gdańsk University of Technology (GUT), 11/12 Narutowicza Street, 80-233, Gdańsk, Poland
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Coronado-Castellote L, Jiménez-Soriano Y. Clinical and microbiological diagnosis of oral candidiasis. J Clin Exp Dent 2013; 5:e279-86. [PMID: 24455095 PMCID: PMC3892259 DOI: 10.4317/jced.51242] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Accepted: 09/26/2013] [Indexed: 12/23/2022] Open
Abstract
Introduction: Candidiasis or oral candidiasis is the most frequent mucocutaneous mycosis of the oral cavity. It is produced by the genus Candida, which is found in the oral cavity of 53% of the general population as a common commensal organism. One hundred and fifty species have been isolated in the oral cavity, and 80% of the isolates correspond to Candida albicans, which can colonize the oral cavity alone or in combination with other species. Transformation from commensal organism to pathogen depends on the intervention of different predisposing factors that modify the microenvironment of the oral cavity and favor the appearance of opportunistic infection.
The present study offers a literature review on the diagnosis of oral candidiasis, with the purpose of establishing when complementary microbiological techniques for the diagnosis of oral candidiasis should be used, and which techniques are most commonly employed in routine clinical practice in order to establish a definitive diagnosis.
Materials and methods: A Medline-PubMed, Scopus and Cochrane search was made covering the last 10 years.
Results: The diagnosis of oral candidiasis is fundamentally clinical. Microbiological techniques are used when the clinical diagnosis needs to be confirmed, for establishing a differential diagnosis with other diseases, and in cases characterized by resistance to antifungal drugs. Biopsies in turn are indicated in patients with hyperplastic candidiasis. Staining (10% KOH) and culture (Sabouraud dextrose agar) are the methods most commonly used for diagnosing primary candidiasis. Identification of the individual species of Candida is usually carried out with CHROMagar Candida®. For the diagnosis of invasive candidiasis, and in cases requiring differentiation between C. albicans and C. dubliniensis, use is made of immunological and genetic techniques such as ELISA and PCR.
Key words:Clinical, oral candidiasis, microbiology.
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Affiliation(s)
- Laura Coronado-Castellote
- Dentistry. Master of Oral Medicine and Oral Surgery. Faculty of Medicine and Dentistry. University of Valencia. Spain
| | - Yolanda Jiménez-Soriano
- Associate Professor of the Department of Stomatology. Faculty of Medicine and Dentistry. University of Valencia. Spain
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Kimori H, Yamamoto K, Yamachika S, Tsurumoto A, Kamikawa Y, Sasao M, Morito M, Saito I, Ohshima T, Maeda N, Nakagawa Y. Factors associated with the presence of atrophic tongue in patients with dry mouth. Gerodontology 2013; 32:13-7. [PMID: 23718267 DOI: 10.1111/ger.12045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/30/2013] [Indexed: 11/29/2022]
Abstract
PURPOSE This study aimed to identify factors associated with atrophic tongue in patients with dry mouth. METHODS Discriminant analysis was performed in 1265 patients with dry mouth to identify factors that might influence the risk of developing atrophic tongue. The dependent variable was the presence of atrophic tongue, while patient age, resting saliva flow rate, stimulated saliva flow rate and Candida colony-forming units (CFU) were used as the independent variables. RESULTS The standardised linear discriminant coefficients showed that Candida CFU, stimulated saliva flow rate and age were significantly associated with the presence of atrophic tongue. The following linear discriminant function was obtained: z = 0.024 × age - 0.63 × (resting saliva flow rate) - 0.81 × (stimulated saliva flow rate) + 0.002 × Candida CFU - 0.611. CONCLUSION High Candida CFU, low stimulated saliva flow rate and advanced age were identified as closely associated factors for the risk of development of atrophic tongue.
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Affiliation(s)
- Hisato Kimori
- Department of Clinical Pathophysiology, Tsurumi University Dental Hospital, Yokohama, Japan; Department of Geriatric Dentistry, Tsurumi University School of Dental Medicine, Yokohama, Japan
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16
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Mosci P, Pericolini E, Gabrielli E, Kenno S, Perito S, Bistoni F, d'Enfert C, Vecchiarelli A. A novel bioluminescence mouse model for monitoring oropharyngeal candidiasis in mice. Virulence 2013; 4:250-4. [PMID: 23334179 DOI: 10.4161/viru.23529] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Oropharyngeal Candida albicans (C. albicans) infection usually occurs in patients with altered cell-mediated immune response. Many animal models have been developed for studying the pathogenesis of disease. Here we describe a new model for real-time monitoring of oral candidiasis. Mice were rendered susceptible to oral candidiasis by injection with cortisone acetate. Oral infection was performed by placing a swab saturated with genetically engineered bioluminescent strain of C. albicans sublingually. An in vivo imaging technique, exploiting stably trasformed C. albicans that costitutively express luciferase, was adopted. This novel longitudinal study represents a powerful tool to: (1) test real-time progression of infection, (2) identify the target site of C. albicans in specific organs, (3) evaluate the efficacy of antifungal therapies and (4) explore the spread of C. albicans from the local to systemic compartment in a new way.
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Affiliation(s)
- Paolo Mosci
- Internal Medicine, Department of Pathology, Diagnostic and Veterinary Clinic, University of Perugia, Perugia, Italy
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17
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Kutikhin AG, Yuzhalin AE, Brusina EB. Organ Microbiota in Cancer Development: The Holy Grail of Biological Carcinogenesis. Infect Agent Cancer 2013. [DOI: 10.1007/978-94-007-5955-8_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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18
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Whiley RA, Cruchley AT, Gore C, Hagi-Pavli E. Candida albicans strain-dependent modulation of pro-inflammatory cytokine release by in vitro oral and vaginal mucosal models. Cytokine 2011; 57:89-97. [PMID: 22129624 DOI: 10.1016/j.cyto.2011.10.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 10/07/2011] [Accepted: 10/22/2011] [Indexed: 11/17/2022]
Abstract
Candida albicans is a commensal organism at several sites and is a versatile, opportunistic pathogen. The underlying factors of pathogen and host associated with commensalism and pathogenicity in C. albicans are complex and their importance is largely unknown. We aimed to study the responses of oral epithelial (OEM) and vaginal epithelial models (VEM) to infection by oral and vaginal C. albicans strains to obtain evidence of inter-strain differences in pathogenicity and of site-specificity. Following inoculation of models, proinflammatory cytokines IL-1α, IL-1β, IL-6, IL-8 and prostaglandin E2 (PGE2) release were monitored and histological staining undertaken. Striking differences in strain behaviour and epithelial responses were observed. IL-1α, IL-1β and IL-8 release were significantly increased from the OEM in response to denture stomatitis strain NCYC 1467. Increased IL-8 release also followed infection of the OEM with both vaginal strains. Overall the VEM was relatively unresponsive to infection with either oral or vaginal strains under these conditions. Adherence and hyphal development were observed for all strains on both models although extensive, uniform tissue penetration was seen only with stomatitis strain NCYC 1467 on the OEM. Candidal strains were assayed for phospholipase (PL) and secreted aspartyl proteinase (SAP) activities where phospholipase (PL) activity was highest for strain NCYC 1467 although highest SAP activity was observed for vaginal strain NCPF 8112 in this assay. This is the first study to concurrently investigate cytokine production from oral and epithelial models using candidal strains originating from these respective mucosal sites from healthy and disease states. These data demonstrate significant differences in inflammatory responses of host epithelia to individual C. albicans strains.
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Affiliation(s)
- Robert A Whiley
- Institute of Dentistry, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London E1 2AD, United Kingdom
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19
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Luo DQ, Yang W, Wu LC, Liu JH, Chen WN. Interdigital ulcer: an unusual presentation of Candida infection. Mycoses 2011; 54:e780-4. [PMID: 21615540 DOI: 10.1111/j.1439-0507.2011.02023.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Interdigital ulcer is an exceptionally rare condition while erosio interdigitalis blastomycetica is common for candidiasis. Four Chinese patients with Candida interdigital ulcers were reported. The exudates were examined directly and cultured for fungi. Skin biopsies were stained with haematoxylin-eosin and periodic acid Schiff. There were a man and three women (age range: 34-56 years) who presented with 1- to 3-month history of chronic cutaneous ulcer on the interdigital web of hand or foot. The lesions were located on hand for one woman, and on the left foot for the rest. The patients had poor response to the previous treatment of topical steroids and oral antimicrobials. Candida albicans was isolated from a man and two women, Candida tropicalis from another woman. Biopsy specimens revealed yeast and mycelium as well as inflammatory infiltrate in necrotic tissue in two patients; only inflammatory cells in the other two. The patients had complete remission with oral itraconazole and topical bifonazole cream therapy for 3- to 5-week. Candida species may cause interdigital ulcer on hand or foot. Oral itraconazole and topical bifonazole may be an optional therapy for such an ulcer.
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Affiliation(s)
- Di-Qing Luo
- Department of Dermatology, Huangpu Hospital of The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
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Silva S, Hooper SJ, Henriques M, Oliveira R, Azeredo J, Williams DW. The role of secreted aspartyl proteinases in Candida tropicalis invasion and damage of oral mucosa. Clin Microbiol Infect 2011; 17:264-72. [PMID: 20456460 DOI: 10.1111/j.1469-0691.2010.03248.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Candida virulence attributes include the ability to colonize and invade host tissues, and the secretion of hydrolytic enzymes. Although Candida albicans is regarded as the principal fungi causing infections in humans, other species, particularly Candida tropicalis, are increasingly being recognized as human pathogens. Relatively little is known, however, about the virulence attributes associated with C. tropicalis. The present study aimed to investigate epithelial infection by C. tropicalis using a reconstituted human oral epithelium (RHOE) together with confocal laser scanning microscopy and real-time PCR. A comparison of clinical strains was made in terms of tissue colonization, invasion and C. tropicalis secreted aspartyl proteinase (SAPT) gene expression. All C. tropicalis strains were able to colonize RHOE in a strain-dependent manner. After 12 h of infection, C. tropicalis was found to be highly invasive, with extensive tissue damage occurring after 24 h. Real-time PCR of C. tropicalis SAPT1-4 genes showed that expression was strain-dependent, with SAPT2-4 transcripts being frequently detected and SAPT1 rarely detected. Tissue invasion and damage was not inhibited by the presence of pepstatin A. Accordingly, and given that an increase in infection time was not accompanied with an increase in SAPT gene expression, it can be suggested that the proteinases are not involved in invasion and damage of RHOE by C. tropicalis. In summary, C. tropicalis can be considered as highly invasive with the ability to induce significant tissue damage. These features, however, do not appear to be related to specific SAPT gene expression.
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Affiliation(s)
- S Silva
- Institute for Biotechnology and Bioengineering, Universidade do Minho, Campus de Gualtar, Braga, Portugal
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21
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Williams DW, Kuriyama T, Silva S, Malic S, Lewis MAO. Candida biofilms and oral candidosis: treatment and prevention. Periodontol 2000 2011; 55:250-65. [PMID: 21134239 DOI: 10.1111/j.1600-0757.2009.00338.x] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Mohd Bakri M, Mohd Hussaini H, Rachel Holmes A, David Cannon R, Mary Rich A. Revisiting the association between candidal infection and carcinoma, particularly oral squamous cell carcinoma. J Oral Microbiol 2010; 2. [PMID: 21523221 PMCID: PMC3084579 DOI: 10.3402/jom.v2i0.5780] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Background Tobacco and alcohol are risk factors associated with cancer of the upper aerodigestive tract, but increasingly the role of infection and chronic inflammation is recognized as being significant in cancer development. Bacteria, particularly Helicobacter pylori, and viruses such as members of the human papilloma virus family and hepatitis B and C are strongly implicated as etiological factors in certain cancers. There is less evidence for an association between fungi and cancer, although it has been recognized for many years that white patches on the oral mucosa, which are infected with Candida, have a greater likelihood of undergoing malignant transformation than those that are not infected. Objective This article reviews the association between the development of oral squamous cell carcinoma in potentially malignant oral lesions with chronic candidal infection and describes mechanisms that may be involved in Candida-associated malignant transformation.
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Affiliation(s)
- Marina Mohd Bakri
- Department of Oral Biology, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia
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23
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Silva S, Henriques M, Hayes A, Oliveira R, Azeredo J, Williams DW. Candida glabrata and Candida albicans co-infection of an in vitro oral epithelium. J Oral Pathol Med 2010; 40:421-7. [PMID: 21158929 DOI: 10.1111/j.1600-0714.2010.00981.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Candida albicans is regarded as the leading of candidosis. However, Candida glabrata has emerged as an important pathogen of oral mucosa, occurring both singly or in mixed species infections, often with C. albicans. Compared with C. albicans, little is known about the role of C. glabrata in oral infection. The aim of this study was to examine single and mixed species infection of oral epithelium involving C. glabrata and establish its ability to invade and damage tissue. METHODS A reconstituted human oral epithelium (RHOE) was infected only with C. glabrata, or simultaneously with C. glabrata and C. albicans. The ability of both species to invade the tissue was examined using species specific peptide nucleic acid (PNA) probe hybridization and confocal laser scanning microscopy. Epithelial damage was assessed by measuring lactate dehydrogenase (LDH) activity. RESULTS Candida glabrata strains were able to colonize the RHOE, in a strain dependent manner. Candida glabrata single infection after 12 h, generally revealed no invasion of the RHOE, which contrasted with extensive tissue invasion demonstrated by C. albicans. Mixed infection showed that C. albicans enhanced the invasiveness of C. glabrata, and led to increased LDH release by the RHOE, which paralleled the observed histological damage. CONCLUSIONS The results obtained demonstrating enhanced invasion and increased tissue damage caused by mixed C. glabrata and C. albicans infections have important clinical significance and highlight the need to identify Candida species involved in oral candidosis.
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Affiliation(s)
- Sónia Silva
- Institute for Biotechnology and Bioengineering, Universidade do Minho, Campus de Gualtar 4710-057, Braga, Portugal
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Silva S, Henriques M, Oliveira R, Azeredo J, Malic S, Hooper SJ, Williams DW. Characterization of Candida parapsilosis infection of an in vitro reconstituted human oral epithelium. Eur J Oral Sci 2010; 117:669-75. [PMID: 20121929 DOI: 10.1111/j.1600-0722.2009.00677.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Oral candidosis is a common problem in immunocompromised patients, and whilst Candida albicans is regarded as the principal cause of infection, other non-Candida albicans Candida (NCAC) species are increasingly being recognized as human pathogens. Relatively little is known about the virulence factors associated with NCAC species, and the aim of this study was to use a reconstituted human oral epithelium (RHOE) to examine epithelial infection withCandida parapsilosis. Strains originating from the oral and vaginal mucosa and from the urinary tract were all shown to colonize RHOE in a strain-dependent manner. Strain differences were found in the colonizing morphology and in the extent of invasion of the RHOE. Low invasion of RHOE was detected for strains after 12 h, whereas extensive tissue damage was evident after 24 h when assessed using histological examination and lactate dehydrogenase activity determination. Tissue damage was reduced in the presence of pepstatin A, although C. parapsilosis invasion of the tissue was not inhibited. Real-time polymerase chain reaction of secreted aspartyl proteinase (SAP) genes (SAPP1-3) showed that expression was strain dependent, with an increased expression generally occurring for Candida infecting RHOE compared with planktonic equivalents. In summary, C. parapsilosis was not highly invasive of RHOE but did induce significant tissue damage, which could relate to specific SAPgene expression.
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Affiliation(s)
- Sónia Silva
- Institute for Biotechnology and Bioengineering, Universidade do Minho, Braga, Portugal
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25
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Sampaio P, Santos M, Correia A, Amaral FE, Chavéz-Galarza J, Costa-de-Oliveira S, Castro AG, Pedrosa J, Pais C. Virulence attenuation of Candida albicans genetic variants isolated from a patient with a recurrent bloodstream infection. PLoS One 2010; 5:e10155. [PMID: 20405013 PMCID: PMC2854149 DOI: 10.1371/journal.pone.0010155] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Accepted: 03/18/2010] [Indexed: 11/18/2022] Open
Abstract
The incidence of Candida albicans infections and the relapse episodes after antifungal treatment have increased in recent decades. Recurrences are mainly due to the persistence of the original infecting strain that may present genetic and genomic rearrangements during interaction with the host, reflecting strain adaptation. In this study, four isolates recovered from a patient during recurrent candidemia episodes were genotyped by microsatellite length polymorphism (MLP) and by multilocus sequence typing (MLST) and found to be genetic variants of the same strain. Using experimental mouse infections, a progressive reduction in the virulence of the four isolates was observed, with the first two isolates more virulent than the third and fourth. Additionally, in the mouse model, the first isolate resisted host control more efficiently, resulting in higher kidney fungal burdens and necrosis as compared to the third isolate. The resolution of inflammation was delayed in mice challenged with the first isolate and the message for IFN-gamma and TNF-alpha in the spleen was lower within the first few hours post-infection. Original and recurrent isolates also displayed different phenotypes regarding activity of secreted enzymes and response to stress agents. Overall, the comparative analysis indicated that the virulence decrease of these isolates was related to a lower ability to resist to the host anticandida effector mechanisms. We showed for the first time that C. albicans genetic variants of the same strain, sequentially isolated from an immunocompromised patient, underwent adaptations in the human host that resulted in virulence attenuation when tested in mice.
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Affiliation(s)
- Paula Sampaio
- Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, Braga, Portugal
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26
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Abstract
Candida species are common pathogens causing superficial mycoses primarily affecting the mucosa and the skin in humans. Crucial steps during pathogenesis of superficial candidiasis comprise fungal adhesion, colonisation and subsequent penetration of the respective tissues. Exploring these pathological events and perhaps fungal and tissue responses towards drug treatment is imperative in the management of this infection. Unfortunately, pathological biopsies of superficial candidiasis do not exhibit the early changes in the host-pathogen interaction as the tissues are already invaded by the fungi. In vivo experimental assessments of pathological processes of superficial candidiasis are also limited because of the difficulties in providing reproducible and comparable conditions in the host environment. Conversely, in vitro models have helped studying fungal-host interactions under more defined and controlled conditions. Some common in vitro models used to simulate superficial candidiasis are chick chorioallantoic membrane, mucosal explants and single layer or multiple layer cell cultures. Interestingly, these experimental approaches share advantages as well as disadvantages when compared with in vivo conditions. Hence, this review intends to discuss about the experimental superficial candidiasis produced in various tissue models and their advantages as well as disadvantages with a particular reference to further improvement of validity and reliability of such experiments.
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Affiliation(s)
- J A M S Jayatilake
- Division of Microbiology, Faculty of Dental Sciences, University of Peradeniya, Peradeniya, Sri Lanka.
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27
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Hooper SJ, Wilson MJ, Crean SJ. Exploring the link between microorganisms and oral cancer: a systematic review of the literature. Head Neck 2009; 31:1228-39. [PMID: 19475550 DOI: 10.1002/hed.21140] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The majority of cases of oral cancer have been related to tobacco use and heavy alcohol consumption. However, the incidence of oral cavity carcinoma appears to be increasing in many parts of the world in a manner that it is difficult to explain with traditional risk factors alone. Meanwhile, interest in the possible relationships between microorganisms and the different stages of cancer development has been rising and numerous mechanisms by which bacteria and yeast may initiate or promote carcinogenesis are currently under investigation. In particular, a persuasive body of evidence suggests a possible etiological role involving the metabolism and production of carcinogenic products, such as acetaldehyde. Other suggested mechanisms include the induction of chronic inflammation and direct interference with eukaryotic cell cycle and signaling pathways. This review aims to summarize the known associations between microbial infection and cancer and draw attention to how they may relate to oral carcinoma.
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Affiliation(s)
- Samuel J Hooper
- Tissue Engineering and Reparative Dentistry, School of Dentistry, Cardiff University, Heath Park, Cardiff, CF14 4XY, United Kingdom.
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Expression levels of a filament-specific transcriptional regulator are sufficient to determine Candida albicans morphology and virulence. Proc Natl Acad Sci U S A 2008; 106:599-604. [PMID: 19116272 DOI: 10.1073/pnas.0804061106] [Citation(s) in RCA: 166] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Candida albicans, the major human fungal pathogen, undergoes a reversible morphological transition from single yeast cells to pseudohyphal and hyphal filaments (elongated cells attached end-to-end). Because typical C. albicans infections contain a mixture of these morphologies it has, for many years, been difficult to assess the relative contribution of each form to virulence. In addition, the regulatory mechanisms that determine growth in pseudohyphal and hyphal morphologies are largely unknown. To address these questions we have generated a C. albicans strain that can be genetically manipulated to grow completely in the hyphal form under non-filament-inducing conditions in vitro. This was achieved by inducing high-level constitutive expression of UME6, a recently identified filament-specific transcriptional regulator of C. albicans hyphal extension. We show that high-level UME6 expression significantly increases hyphal formation and promotes virulence in a mouse model of systemic candidiasis. Our results strongly suggest that shifting the morphology of a C. albicans population toward the hyphal form, and/or increasing hyphal-specific gene expression, during the course of infection is sufficient to improve virulence potential. We also demonstrate that lower levels of UME6 expression specify growth largely in the pseudohyphal form and that increasing UME6 levels is sufficient to cause cells to gradually shift from pseudohyphal to hyphal morphology. In addition, we show that UME6 levels differentially induce the expression of several known filament-specific transcripts. These findings suggest that a common transcriptional regulatory mechanism functions to specify both pseudohyphal and hyphal morphologies in a dosage-dependent manner.
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29
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Thewes S, Moran GP, Magee BB, Schaller M, Sullivan DJ, Hube B. Phenotypic screening, transcriptional profiling, and comparative genomic analysis of an invasive and non-invasive strain of Candida albicans. BMC Microbiol 2008; 8:187. [PMID: 18950481 PMCID: PMC2579918 DOI: 10.1186/1471-2180-8-187] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Accepted: 10/24/2008] [Indexed: 01/12/2023] Open
Abstract
Background Invasion of host tissue by the human fungal pathogen Candida albicans is an important step during the development of candidosis. However, not all C. albicans strains possess the same invasive and virulence properties. For example, the two clinical isolates SC5314 and ATCC10231 differ in their ability to invade host tissue and cause experimental infections. Strain SC5314 is invasive whereas strain ATCC10231 is non-invasive and strongly attenuated in virulence compared to SC5314. In this study we compare the in vitro phenotypic, transcriptional and genomic profiles of these two widely used laboratory strains in order to determine the principal biological and genetic properties responsible for their differential virulence. Results In all media tested, the two strains showed the same metabolic flexibility, stress resistance, adhesion properties and hydrolytic enzyme secretion in vitro. However, differences were observed in response to cell-surface disturbing agents and alkaline pH. Furthermore, reduced hyphal formation in strain ATCC10231 under certain conditions correlated with reduced invasive properties in an in vitro invasion assay and a reduced ability to invade epithelial tissue. Despite these diverse phenotypic properties, no substantial genomic differences were detected by comparative genome hybridisation within the open reading frames. However, in vitro transcriptional profiling displayed major differences in the gene expression of these two strains, even under normal in vitro growth conditions. Conclusion Our data suggest that the reason for differential virulence of C. albicans strains is not due to the absence of specific genes, but rather due to differences in the expression, function or activity of common genes.
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Affiliation(s)
- Sascha Thewes
- Division FG16 Mycology, Robert Koch Institute, Berlin, Germany.
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30
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Ali A, Natah S, Konttinen Y. Differential expression of Toll-like receptors in chronic hyperplastic candidosis. ACTA ACUST UNITED AC 2008; 23:299-307. [DOI: 10.1111/j.1399-302x.2007.00428.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Banerjee M, Thompson DS, Lazzell A, Carlisle PL, Pierce C, Monteagudo C, López-Ribot JL, Kadosh D. UME6, a novel filament-specific regulator of Candida albicans hyphal extension and virulence. Mol Biol Cell 2008; 19:1354-65. [PMID: 18216277 PMCID: PMC2291399 DOI: 10.1091/mbc.e07-11-1110] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Revised: 01/03/2008] [Accepted: 01/10/2008] [Indexed: 11/11/2022] Open
Abstract
The specific ability of the major human fungal pathogen Candida albicans, as well as many other pathogenic fungi, to extend initial short filaments (germ tubes) into elongated hyphal filaments is important for a variety of virulence-related processes. However, the molecular mechanisms that control hyphal extension have remained poorly understood for many years. We report the identification of a novel C. albicans transcriptional regulator, UME6, which is induced in response to multiple host environmental cues and is specifically important for hyphal extension. Although capable of forming germ tubes, the ume6Delta/ume6Delta mutant exhibits a clear defect in hyphal extension both in vitro and during infection in vivo and is attenuated for virulence in a mouse model of systemic candidiasis. We also show that UME6 is an important downstream component of both the RFG1-TUP1 and NRG1-TUP1 filamentous growth regulatory pathways, and we provide evidence to suggest that Nrg1 and Ume6 function together by a negative feedback loop to control the level and duration of filament-specific gene expression in response to inducing conditions. Our results suggest that hyphal extension is controlled by a specific transcriptional regulatory mechanism and is correlated with the maintenance of high-level expression of genes in the C. albicans filamentous growth program.
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Affiliation(s)
- Mohua Banerjee
- *Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900
| | - Delma S. Thompson
- *Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900
| | - Anna Lazzell
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249; and
| | - Patricia L. Carlisle
- *Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900
| | - Christopher Pierce
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249; and
| | - Carlos Monteagudo
- Department of Pathology, Universidad de Valencia, 46010 Valencia, Spain
| | - José L. López-Ribot
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249; and
| | - David Kadosh
- *Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900
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Jayatilake JAMS, Samaranayake YH, Samaranayake LP. A comparative study of candidal invasion in rabbit tongue mucosal explants and reconstituted human oral epithelium. Mycopathologia 2008; 165:373-80. [PMID: 18320346 DOI: 10.1007/s11046-008-9096-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Accepted: 02/14/2008] [Indexed: 11/24/2022]
Abstract
The purpose of this study is to compare the light and scanning electron microscopic (SEM) features of tissue invasion by three Candida species (C. albicans, C. tropicalis, and C. dubliniensis) in two different tissue culture models: rabbit tongue mucosal explants (RTME) and reconstituted human oral epithelium (RHOE). Tongue mucosal biopsies of healthy New Zealand rabbits were maintained in explant culture using a transwell system. RHOE was obtained from Skinethic Laboratory (Nice, France). RTME and RHOE were inoculated with C. albicans, C. tropicalis, and C. dubliniensis separately and incubated at 37 degrees C, 5% CO(2), and 100% humidity up to 48 h. Light microscopic and SEM examinations of uninfected (controls) and infected tissues were performed at 24 and 48 h. C. albicans produced characteristic hallmarks of pathological tissue invasion in both tissue models over a period of 48 h. Hyphae penetrated through epithelial cells and intercellular gaps latter resembling thigmotropism. SEM showed cavitations on the epithelial cell surfaces particularly pronounced at sites of hyphal invasion. Some hyphae on RTME showed several clusters of blastospores attached in regular arrangements resembling "appareil sporifere". C. tropicalis and C. dubliniensis produced few hyphae mainly on RTME but they did not penetrate either model. Our findings indicate that multiple host-fungal interactions such as cavitations, thigmotropism, and morphogenesis take place during candidal tissue invasion. RTME described here appears to be useful in investigations of such pathogenic processes of Candida active at the epithelial front.
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Affiliation(s)
- J A M S Jayatilake
- Microbiology, Department of Oral Medicine and Periodontology, Faculty of Dental Sciences, University of Peradeniya, Peradeniya, Sri Lanka.
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Hisajima T, Ishibashi H, Yamada T, Nishiyama Y, Yamaguchi H, Funakoshi K, Abe S. Invasion process ofCandida albicansto tongue surface in early stages of experimental murine oral candidiasis. Med Mycol 2008; 46:697-704. [DOI: 10.1080/13693780802039919] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Thewes S, Kretschmar M, Park H, Schaller M, Filler SG, Hube B. In vivo and ex vivo comparative transcriptional profiling of invasive and non-invasive Candida albicans isolates identifies genes associated with tissue invasion. Mol Microbiol 2007; 63:1606-28. [PMID: 17367383 DOI: 10.1111/j.1365-2958.2007.05614.x] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The human pathogenic fungus Candida albicans can cause a wide range of infections and invade multiple organs. To identify C. albicans genes that are expressed during invasion of the liver, we used genome-wide transcriptional profiling in vivo and ex vivo. By analysing the different phases of intraperitoneal infection from attachment to tissue penetration in a time-course experiment and by comparing the profiles of an invasive with those of a non-invasive strain, we identified genes and transcriptional pattern which are associated with the invasion process. This includes genes involved in metabolism, stress, and nutrient uptake, as well as transcriptional programmes regulating morphology and environmental sensing. One of the genes identified as associated with liver invasion was DFG16, a gene crucial for pH-dependent hyphal formation, correct pH sensing, invasion at physiological pH and systemic infection.
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Affiliation(s)
- Sascha Thewes
- Division Mycology, Robert-Koch Institute, Berlin, Germany
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Malic S, Hill KE, Ralphs JR, Hayes A, Thomas DW, Potts AJ, Williams DW. Characterization of Candida albicans infection of an in vitro oral epithelial model using confocal laser scanning microscopy. ACTA ACUST UNITED AC 2007; 22:188-94. [PMID: 17488445 DOI: 10.1111/j.1399-302x.2007.00344.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Oral candidosis presents as several distinct forms and one of these, chronic hyperplastic candidosis, is distinguished by penetration of the epithelium by Candida. The aim of this study was to use confocal laser scanning microscopy to examine invasion of the oral epithelium by Candida albicans from different oral conditions and to determine whether inherent strain differences exist that could relate to infection type. Reverse transcription-polymerase chain reaction was also used to detect products from virulence gene families. METHODS C. albicans (n = 19) was used to infect reconstituted human oral epithelium, which was incubated for 12 h. One half of the reconstituted human oral epithelium was then fixed and stained with concanavalin A-Alexa 594, pan-cytokeratin antibody-Alexa 488 and Hoechst nucleic acid dye. RNA was extracted from the remaining tissue for reverse transcription-polymerase chain reaction targeting secreted aspartyl proteinase, phospholipase and agglutinin-like sequence genes of C. albicans. RESULTS Confocal laser scanning microscopy revealed strain-dependent tissue invasion, with differences evident in surface colonization, C. albicans morphology and the extent and pattern of tissue penetration. Hyphae were seen to directly penetrate epithelial cells and migrate between keratinocytes with yeast budding also evident in the reconstituted human oral epithelium. A relationship between 'high tissue invasion' and expression of secreted aspartyl proteinase genes 4-6 was noted. Interestingly, four of the five 'high invaders' originated from chronic hyperplastic candidosis. CONCLUSIONS Confocal laser scanning microscopy permitted high resolution analysis of reconstituted human oral epithelium invasion by C. albicans and identified strain differences in the invasion process. Association between extensive hyphal morphology, direct epithelial penetration and high surface colonization were made with the 'highly invasive' strains.
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Affiliation(s)
- S Malic
- Oral Surgery, Medicine & Pathology, School of Dentistry, Heath Park, Cardiff, UK
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Xi L, Li X, Zhang J, Lu C, Xie T, Yin R. Good response in a patient with deep-seated subcutaneous ulcer due to Candida species. Mycopathologia 2007; 164:77-80. [PMID: 17551846 DOI: 10.1007/s11046-007-9030-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2007] [Accepted: 05/16/2007] [Indexed: 10/23/2022]
Abstract
Deep-seated subcutaneous ulcers infected with Candida species are rare. We are reporting a 51-year-old Cantonese woman who had a large, deep-seated subcutaneous ulcer on her right shoulder for more than a year. Direct smears of the purulent extrusion revealed many pseudohyphae and yeast cells. Candida species were isolated from the purulent extrusion and further identified as Candida albicans and C. parapsilosis. A skin lesion biopsy contained yeast cells and pseudohyphae. C. parapsilosis were once isolated from the biopsy specimen. Total healing was obtained with itraconazole (200 mg twice daily for 16 days and then 100 mg twice daily for 14 days) combined with phototherapy.
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Affiliation(s)
- Liyan Xi
- Department of Dermatology, The Second Affiliated Hospital, Sun Yat-Sen University, 107 West Yanjiang Rd, Guangzhou, 510120, China.
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Ali A, Rautemaa R, Hietanen J, Beklen A, Konttinen Y. A possible CD1a Langerhans cell-mast cell interaction in chronic hyperplastic candidosis. J Oral Pathol Med 2007; 36:329-36. [PMID: 17559493 DOI: 10.1111/j.1600-0714.2007.00527.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS T lymphocyte-antigen-presenting cell (APC) interaction plays a central role in T lymphocyte activation and APC maturation. We therefore studied the CD1a-positive Langerhans cells with respect to receptor activator of nuclear factor kappa B ligand (RANKL)-positive cells in chronic hyperplastic candidosis (CHC). MATERIALS AND METHODS Tissue sections of CHC were compared with leukoplakia and healthy oral mucosa using RANKL and CD1a monoclonal antibodies in an avidin-biotin peroxidase complex protocol. Two different antigen-retrieval protocols, pepsin preincubation and Tris-EDTA heat treatment, were used. RESULTS CD1a-positive Langerhans cells were in healthy and leukoplakia epithelium found in the middle layer, but in CHC in all layers of the epithelium, at the basement membrane and as mononuclear round cells in the lamina propria. Use of pepsin digestion enabled studies of mast cells and their activation in the form of degranulation of RANKL. CONCLUSIONS The numerical, morphological and topographical versatility of the CD1a-positive Langerhans cells in CHC can be clarified by dendritic cell (DC) recruitment into the epithelium. RANK-positive and RANKL-sensitive DCs have ample opportunity to interact with local T lymphocytes. Use of an optimized antigen-retrieval protocol enabled demonstration of an active engagement (degranulation) of mast cells, which represent a rapidly available source of soluble RANKL.
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Affiliation(s)
- Ahmed Ali
- Department of Anatomy/Biomedicum, University of Helsinki, Helsinki, Finland
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Jayatilake JAMS, Samaranayake YH, Cheung LK, Samaranayake LP. Quantitative evaluation of tissue invasion by wild type, hyphal and SAP mutants of Candida albicans, and non-albicans Candida species in reconstituted human oral epithelium. J Oral Pathol Med 2006; 35:484-91. [PMID: 16918600 DOI: 10.1111/j.1600-0714.2006.00435.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Oral candidiasis is a common problem in compromised patients. Although several non-albicans Candida species have emerged as pathogens the majority of candidal infections are caused by Candida albicans. Morphogenesis from the blastospore to filamentous phase, and production of secretory aspartyl proteinases (SAP) are two major virulence attributes of these opportunistic yeast. Histopathology of oral candidiasis is characterized by fungal invasion of the superficial epithelium although the invasive potentials of different Candida species vary. Computerized image analysis systems (IAS) utilizing immunohistochemistry have been successfully employed for quantification of such histopathological features. The purpose of this study was to evaluate quantitatively the in vitro invasive potential of C. albicans and its hyphal and SAP mutants, and five other non-albicans Candida species using a computerized IAS. METHODS In vitro human oral candidiasis was produced using five wild type and one reference C. albicans isolates, hyphal and SAP mutants of C. albicans SC 5314, and one wild type and one reference isolate each of C. tropicalis, C. dubliniensis, C. glabrata, C. parapsilosis and C. krusei in a reconstituted human oral epithelium (RHOE) model. The infected tissues were examined histologically at 12, 24 and 48 h. Invading fungal elements were visualized by periodic acid-Schiff (PAS) staining and quantitatively evaluated as a percentage of total tissue invasive area, using a computerized IAS. RESULTS All C. albicans isolates including hyphal mutant cph1/cph1 and SAP mutants; sap 1-3, sap 4-6 produced hyphae and differentially (P < 0.05) invaded the tissue over 48 h. The invasive potential of hyphal mutant cph1/cph1 and SAP mutants (sap 1-3, sap 4-6) were similar to the parent wild-type isolate at 12 h although after 24 h their invasion was dissimilar (P < 0.05). Non-albicans Candida species and hyphal mutants; efg1/efg1, efg1/efg1 cph1/cph1 were all non-invasive. CONCLUSIONS RHOE model in combination with computerized image analysis permits for the first time, the assessment of invasive potential of Candida species in a quantitative manner. The differential tissue invasive patterns of various C. albicans isolates, their mutants and other Candida species are also described.
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Affiliation(s)
- J A M S Jayatilake
- Division of Microbiology, Faculty of Dental Sciences, University of Peradeniya, Peradeniya, Sri Lanka
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Current awareness on yeast. Yeast 2005; 22:593-600. [PMID: 16003861 DOI: 10.1002/yea.1163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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